Metal soeew machine



` (No Model.) l 4 Sheets-Sheet 2.

` A'. JOHNSTON.

METAL SCREW MAGHINR No. 293,176. Patented Feb. 5, 1884.

(No Model.) i 4'Sheets-Sheet 3v.

A. JOHNSTDN.

l METAL SCREW MACHINE. No. 293,176.. Patented Feb. 5. 1884.

NITE

Starlets 1Arr3Nfr ALLEN JOHNSTON, or Orrmviwn, iowa.

METAL-SCREW MACHINE. j

SPECIFICATION forming Apart of Letters Patent No. 293,176, dated February 5, 1884.

l `Application led July 31,1883. (No model.)

fo mZZwtom ani/ay concern.:

Ottumwa, in the county of Vapelloand State of Iowa, have invented a new and useful Im` provement in `MetaleSorew Machines, which improvenpxent i s fully set forth `in lthe follow-g ing specification. u

This invention relates more particularly tol machines formaking screws from along rodor screw-stock by a series of operations performed automatically; butit is in part applicable to.' machines not wholly automatic in their acti on,-`

and to machines for making other articles.

' It consists, first, in the co1nbination,with the threading -die, of` a pointing-tool separately supported, and arranged to project from the rear-into the hollow center of the die. Heretofore a pointing-tool has been combined with athreading-die, the saine being supported in the shank ofthe die or threading-tool, and connected therewith by a spline and groove, so that neither can turn independently of the other.

The'pointing-instrument, or cutter for shaping the point, and the die or cutter for turning the thread, are, in fact, so connected as to form one tool. v In this invention they are substantially separate tools, but adapted for conjoint operation.V This part of the invention also co1n prises the'` combination, with a rotary die, of a non-rotating pointing-tool arranged in line with the axis ofthe die. One of the principal advantages of supporting the pointing-tool thepointing-tool may be held to its work posiseparately from the die by means outside the same is, that therebythe two tools may be adapted to cut at different speeds. There the pointing-instrument is connected with the shank of the die, as heretofore, the movement of rotation around the blank or screw-stock is the same for both die and pointinginstrument, V

and if the latter be held from independent longitudinal movement it must advance at equal speedwith the die, and turnloii the end ofthe blank as fast a`s it is threaded. To obviate the last difficulty, the pointing-instrument has heretofore been held to its work by elastic or yielding pressure, and not positively. The present improvement renders it unnecessary to resort to this expedient, (which has the Vdisadvantage of leaving the screws unequal in length, or, at least, being liableto do so,) since lwith the threading operation.

tively. It will be shown herein as thus held Be it knownrthat I, ALLEN JOHNSTON, of

to its work.

Theinvention secondly consists in com- ',bining the mechanism for threading the screw stock or blankand` pointing the same while the die, is on the screw with mechanism for Vturning down the rodin advance ofthethreading-die, and, in part at least, simultaneously This latter mechanism may be of the special construction Vshown in Letters Patent No. 269,7 90, granted to me December 26, 1882, or ot' other suitable construction adapted to the purpose, such as that hereinafter described.

The invention thirdly consists in mechanism for withdrawing the turningdown tool,

'after its cutting is accomplished, by moving it backward a shortdistance and then aside, thus leaving the under side ofthe head smooth and t without burr., In my above-mentioned patent the slide carrying the turning-down tool moves in oblique ways. This part` ofthe invention may beconsidered Aan .improvement on that arrangement.

The invention fourthly consists in an adjustablelength-gage supported on the machineframe or stationary part of the machine, and movable across the aXisOf the chuck, in combi'- nation with the meohanisln for relieving and restoring the bite ofthe chuck-jaws and for automatically introducing the gage in front of the chuck when so relieved. A spring or weight advances the long rod or screw-stock at this moment. The adjustment has for its object to enable wear to be taken up or 'comesV pensated for, and also to regulate thefeed of" the rod or stock to suit different sizes of screws. In Letters Patent No. 269,791, granted to me December`26, 1882, a similar combination is described without the feature of adjustment of the length-gage- This part of the invention may therefore be considered as an improvement upon the construction therein. It comprises, also, the supporting of the length-gage upon a journal pin or shaft, instead ofin ways or grooves, as shown in' said patent. e vious that the journal pin or shaft could be used even if the feature of adjustment be omitf ted; but its use allows the adjiistment to--be most easily effected'.

It is ob- The invention ifthly consists in retaining,

or retaining and adjusting, the jaws of a screwcutting die having the jaws formedin one piece by pressure applied at the points on the periphery, opposite or about opposite the eutting-edges of each jaw, the other partsv of the jaw being left free or comparatively free, so that the jaws are by unequal application of pressure twisted slightly on their longitudinal axes, and the cutting-edges thus brought nearer the center, so as to se'cure a clearance for the die. Preferably the jaws are held in bya ring screwed thereon, as described in the patent first referred to, and the application of the pressure to the jaws on the side of the cuttingedges is secured by cutting away each jaw eX- oepton that side, but the jaws could be held in by a plain ring driven onto the die, or by a split ring, or by other means, and the application of pressure to the jaws at one side, instead of equally all over the back, could. be secured, without cutting them away on the outside,by h aving suitable projections on the j aws or on the ydevices for holding them in. The

. advantage attained by this improvement is that the die cuts easier and lasts longer. The jaws may be straight on one side and inclined on the other, as described in my first-named patent; or they may be inclined on both sides. rllhe number of jaws on the die may be varied.

The invention further comprises certain par* ticular constructions and combinations, hereinafter specied, among which the following may be briefly mentioned, to wit: the supporting ofthe turning-down tool on a rockshaft, the construction of the mechanism forv revolving` the threading-die so as to have an axial opening for the introduction o f the pointing-tool, the supporting of the die upon an auxiliary slide carried by the main longitudinal slide upon which the pointing-tool is independently supported, and a slotted tube for supporting the rear end of the rod or. screw stock which projects beyond the end of the chuck-spindle.

The following is a description of the best mode which I have contemplated of applying the principle of the invention, reference being had to the accompanying drawings, which form a part of this specification.

Figure lis a vertieal'longitudinal section of an automatic screw-machine constructed in accordance with the invention; Fig. l, a similar View of a part at the extreme left of the machine as viewed in Fig. l and omitted from said figure; Fig. 2, a plan l(partly in horizontal section on line x x, Fig. l) of the end of the A machine which carries the cutting-tools, and

Figs. 3, 4, 5, 6, and?, vertical cross-sections on lines y y, .e z, o o, w w, and t t, respectively, and in elevatiomlooking in the direction of the arrows upon each section-line. Fig. 8 is a partial view, in longitudinal section, ina plane back of that of Fig. 1. Figs. 9 and 10 are respectively a face view and a perspective of the screw-cutting die detached.

The main or cam shaft A is journaled in bearingsin the machine-frame B, and is driven from the chuck-spindle C through a train of.l

spur-gears, l, 2, 3, 4, 5, 6,- 7, 8, and 9, the chuck-spindle being revolved by a belt on pulley D. The chuck is or may be of any ordinary or suitable construction. As shown, it has a solid head, a, and contains a sliding tube, b, having a series of wedges formed on the front (right-hand, Fig. l) end thereof, a spring, c, for pressing forward said tube b, a block or slotted tube, c2, fixed in the head and forming stay-pieces between the wedges, and chuck-jaws d,formed in one piece and screwed at the rear end into said block, as fully described in Lett-ers Patent No. 261,816, granted to me July 25, 1882. The friction-tube of said patent has been omitted 5 but it or other suitable friction devices may be used. rlhe sliding tube b is at intervals withdrawn through the lever E, pivoted to the machine-frame by the cam F on shaft A, and when released by said cam is restored by the springe. Other mechanism of ordinary or suitable construction for releasing and restoring the bite of the chuck-jaws could be used instead. W'henthe bite of the jaws is released, the rod or stock e is advanced by the weight G, which is suspended in the bight of a cord, f, attached at one end to a stationary part of the machine, and, after passing over pulleys or through guides, connected at the other end with the rod or screw-stock. The rear end of the said rod or screw-stock is supported loosely in the tube H, which is supported by brackets from the parallel bar I, iixed to the machine-frame, and is slotted underneath to allow the passage of the projection or arm g' of the slide Kif. It is through this slide that the cord f is connected with the rod or screw-stock, it (the cord) being fastened in the projection or arm g, and the end of the slide bearing against the end of the screw-stock, so as to advance it when required'. The slide, as shown, is in the form of a rod equal or about equal in diameter to the screw-stock e, and the projection or arm g is at the rear end of it. The object of this is to enable the slide or'rod to enter the hollow chuck-spindle and advance the screwstock until it is all or nearly all used up. It is not, however, essential to use a feed-rod, since a succeeding screw-stock will 'push along the one infront of it afterthe outer end ofthe latter'has entered the chuck-spindle. rlhe distance which the screw-stock shall be advanced at each feed is determined by the length-gage K, which is supported on thestationary journal pin or shaft L, Figs. 2, 5, and 6, and is vibrated thereon across the axis of the chuck by the crank-pin h on the disk M, which is keyed to the main or cam shaft A. The spiral tension-spring N removes it from in front of the chuck when it is released by the crank -'pin h. Of course this release takes place when the bite of. the chuckjaws has been restored. The hub of the gage is free to turn on the journal-pin L, but is prevented from movement lengthwise thereof by the nuts i on either side of the hub. These nuts, be-

I OC

eee,

ing adjustable, permit the adjustment ofthe length f'gage. The crank-pin l1. is of such length and is so arranged that;` it strikes the lower end of the gage in all its positions of adjustinent.` The journal-pin L fits at the ends iinreeessesin` themachine-frame,and is held from endwise motion by the nuts k, which are `screwed up `after the journal-pin has been inserted `inthe recesses. The slide I), which car 1o ries the turning-down tool Q., the die or thread- .ing tool R,.and the pointingtool S, is reciprocated inlongitudinal ways of the machine-` frame by the cam-groovel in the periphery of drum T, which is keyed on the main shaft A. i 5 A pin, un, fixed in said slide P, projects into theHcam-groove Z. The turning-down tool Q `is not carried directly by the longitudinal slide P, but is held in an arm, a, of the rockshaft U, which is journaled in bearings in said 2o slide I. The rock-shaft Uat its outer (right` hand, Figs, l and 2) end is turned down and threadedwith a coarse, strong thread, and it 4 isprovided at the inner end of the threaded portion with a tooth, 1). `Upon the threaded 2 5 portion is a nut or internally-threaded sleeve, NV, which is .prevented from end motion by the fixed collar q, between it andthe holding-4 screw r, but is free to turn with the rockshaft, and to a slight extent independently 3o of it, the independent movement producing through the-screw-thread a slight longitudinal movement of the rock-shaft. There is a tooth, s, on sleeve Vcorresponding to the tooth p on therock-shaft. Onthe under side of the rock-shaft is a projection, 1%, whichis held normallyr against the stopscrew Iu by a spiral compression-spring, X, inclosed in the twofpart` casing a at- (SeefFig. 3.) The lower part, a, of the casing is free to slide 'upon the 4o part a, and has at .its lowerend a spherical head, which fits in a spherical recess in the projection ft, thus making a universal `joint l at thatpoint, while .the upper end of the partA a is pointed and ftsin a conical recess in the` wall of the slide. 'The casing thus adapts it self toall the movements of the rock-shaft. j h V-hen the projectionit: is against the stop u.,

, i as shown, the turning-down tool will `bethrown` forward in the `proper position for turning f 5o down the rod or screwstock. `The proper position can` be attained with great nicety bythe adjustment of the stop u and the proper 'setting of the tool Q inlarm a. The sleeve )V is provided witha depending arm, b', which projects into the path ofthe aroshaped eam'Y, bolted to and movable with the disk Z, the lat ter being fixed to and revolving with the drum T upon the main shaft A.` The cam` or are Y, striking the` armb, `turns the sleeve XV until 6o the tooths strikes .the tooth p, when it turns also the rock-shaft U,movingthe turning-down tool Q away fromthe screw-stock. Vhile the j cam or` are Y is passing under the arm b', it re- `tains.` the turning-downtool in this position, i and during this time the slide Pfand with it,-

` j of' course, `the ,sleeve WV, rock-shaft U and turning-down tool)` is returned,` `bythe carni. y

. with the auxiliary slide B.

\ arecess `in the auxiliary slide JB', and confined rock-shaft, so as (by means of the screw-threa d) to move the rock-shaft endwise, and. thus with `draw-the turning-down tool from the head of `the newly-formed screw before it is-moved aside by the further rotation of the sleeve YV. The die R or threading-tool is supported on an auxiliary slide, B', movable in longitudi- Anal ways of' the slide P. The die is hollow, and has s erewcutting jaws formed integral therewith `and adjusted by a ring, l1. Each 'j aw is cut away on the exterior at l2, (see Figs.

9 and 10,) leaving the pressure of the ring 1l upon the points 13 opposite the cutting-edges .let of the die, or, in other words, upon the cut-` ting or front sident the jaws. Thus the cutting-edges 14C are' held in, while the farther edges 1,5 may spring out slightly, the press-- ure of the ring 11 thus giving a slight twistfo the jaws and bringing the cutting-edges 14 nearer thecenter. This position gives a clear! ance to the die,which causes it to cut the thread easier and makes it last longer. The

exterior threaded portion of the jaws is coni IOC tools in a machine wherein the die does not rotate, it isobvious that this support is or may be non-rotatory; b ut if the die is .to rotate, as in the machine shown, and as it is preferred to do, it is securedA in a revolving support,

such as the annular wheel or gear GQ As shown. the die has an exterior flange, c,which is held by the annular screw d, and is further engaged by the pin e', fitting into a `notch in the flange, and effectually preventing the die from turning independently of itssupport. The gear C is journaled in the head of slide l-T, and is revolved at the proper times from the short shaft D through the clutch-piece E', turning with the shaft D', ,and the clutchpiece F/xed to the sleeve G', and carrying the annular gear H, which meshes with the gear C. The` clutch-piece VE has its bearing in the barrel Gr, fixed to the main slide l?, and is held from endwise movement independent of said barrel by a nut oli-the `end of' the said clutch-piece, while the clutchpiece F', sleeve G, and gear Hlare movable The two clutch` pieces are normally held in engagement bythe spiral compression-spring K', (shownin dotted lines, Fig. l, and in full in Fig.` 8,) placed `inl between the screw g', Figs. 1, 3, and 8, tapped into the outer end of the recess, and the pin f', Figs. l, 4, and 8, fixed in the main slide P,

` no endwisemoveinent. Anon-rotating clutchpiece, M', surrounds the sleeve G on the opposite side of the clutch-piece F' from the clutch-piece E'. lt is pressed-in the direction of said clutch-piece F' by the spiral compression-spring N', and is prevented from rotating by the screw or pin h', which lits in a slot, t', and which serves also to limit the movement of the clutch-piece M under the pressure ofthe spring il'. During the advance of the slide P the clutch-piece F' engages the clutch-piece E' andthe die R is revolved in the same direction as the chuck, but

at a higher speed, so as to cut the thread on the portion of the rod or screw-stock which has just been reduced by the turning-down tool. Vhen the thread is cut, the main slide P is drawn sharply back by the cam Z, and the die R being held by its engagement with 'the thread, the auxiliary slide B', together with the sleeve G and clutch -piece F', are held from endwise movement. The clutch-piece E', being carried with the main slide, is thus disengaged, and the die is allowed to revolve with the chuck until the non-rotative clutchpiece M', which also moves back with the main slide P, engages the piece F', when the rotation of the die is arrested, and the continued revolution of the chuck unthreadsit. As soon as the die is released from the thread, the spring K' immediately causes a re-engagement of the clutch-piece E', and the rotation of the die is resumed. The pointing-tools is supported on a cross-piece, P', bolted to the lt is in line with the screwstock, and has its end of the form adapted to give the desired shape to the point of the screw. It projects through the annular wheel or gear C' into the base of the hollow die R. lThe cutting-olf tool Q', for removing the newlyformed screw from the rod or screw-stock, is carried by a cross-slide, R', supported in ways of the machine-frame, and reciprocated by the cam r', formed on the periphery ot' the drum T, throught-he bent lever S', fulcrumed to a bracket which is bolted to the machine-frame,`

and the link or connecting-rod T'. The tool itself is supported on an auxiliary slide, U',

which is adjustable on the slide R' by the screw W', Fig. 6.

The general operation of the machine as a whole will now be described, it being assumed that the rod'or screw-stock has been inserted between the jaws of the chuck, and has been connected properly with the feeding-weight.

the cutting-off tool Q' are sufficiently with;

drawn by the cam r', lever S', and link T', the length-gage K is turned by the crank-pin 7L across the axis of the chuck, and at the samev time the pressure of the chuck-jaws (Z is released by the withdrawal of the sliding tube b by means of the cam F and lever E, so that the feeding-weight G advances the rod or screw-stock until the end strikes the lengthgage K, now immediately in front of the chuck. Vhile the length-gage is still retained in position by the crank-pin h, the sliding tube b is returned by its spring c, and the chuck-V jaws are closed vupon the rod or screw-stock, so that it is held firmly by and revolves with the chuck and chuck-spindle. The slide P, together with the tools carried thereby, is now advanced by the cam Z. rlShe turning-down tool Q first comes into action and reduces the end of the rod or screw-stock. -After it has reduced a sufficient distance, and before it has finished its operation, the threading-die R is brought into action and commences to cut the thread, it being` revolved by the gears I L', shaft D', clutch-pieces E F', sleeve G', and gears H' C in the same direction as the chuck and rod or screw-stock held therein, but at a higher speed. threading-die then proceed together. As the last part of the thread is being cut, the pointing-tool also comes into action and shapes the point. As soon as the turning-down operation is finished, which may'be at the same time with the threading operation, or it maybe sooner, the arc-shaped cam Y turns the sleeve XV, which iirst moves the rock-shaft U and turning-down tool Q, backward, so that the tool is clear of the newly-cut shoulder or screw-head, and then turns the rock-shaf t and moves the tool aside. lf the screw has then been threaded as far as desired, the motion of the slide P is reversed ,zotherwise it continues until the thread has been extended as far as desired--it may be tothe very head. During this time, and during the reverse movement of the slide P, the turning-down tool is held away from the rod or screw-stock by the cam or are Y. ll' the threading is to continue after the turning down has been finished, the pointing-tool is of course properly set to come into action at the end of the threading operation.

The turning-down tool and IOO IIC

The return of the slide P disengages the4 the improved arrangement of die and pointing-tool could be used in machines for threading blanks, a suitable chuckand feed for holding and feeding'a seriesof separate blauks'lchuck-spindle, the cam-shaft, the eamrfor re! being substituted for the one shown. Such chucksa'nd feeds are well known. The tools alsol could be brought into operation by hand insteadof automatically. The arrangement could be used in machines in which" the chuck moves instead ofqthetools, as inthatdescribed in my Patent No.` 267,214, dated November 7, 1882, and it could be used also in other styles of machine. i

Automaticmechanism for feeding and bringing the tools into action is much preferred to that operated inwhole or in` part by hand,

' and its use in combination with the other elebetween the cutting-edges, in combin ation'with ments is considered a special feature of improvement. i

Thelengthgage could be used in various kinds of machines for turning or otherwise forming articles from the end of4 a long rod, andso with the other improvements.

Having now fully described my said invention and the `manner of carrying the same into effect, what I claim is--` 1. The combination, with the chuck, the screw-cutting die, and the pointing-tool arranged in line with the axis of the die, of the devices to which said pointing-tool is attached, the said devices being disconnected from the body of said die, so thatthe pointing-tool constitutes a separate tool, and may by suitable mechanism be made to cut at a different speed from that of the die, substantially as described.

2. The combination, with the chuck, die, and pointing-tool, of the supporting and operating mechanism, vsubstantially' as described, whereby the pointingtool is brought into actioisl while the die' is on the screw-stock, and is made to cut thelatter at a different speed of rotation from that of the die, as set forth.

8. The vhollow' screw-cutting die having the cutting-jaws formed in one piece with the body of the die, and provided with an opening in said body of greater diameter than `the space the annular or perforated support forholding the die by the periphery, as explained, so that a pointing-tool can be introduced through said opening into position for acting upon the stock in process oi' threading, substantially as described.

4. The combination, with the chuck', the die, and. the pointing-tool arranged in line with the die, of the mechanism4 for holding the pointing-tool to its work rigidly and positively instead of by yielding pressure,.sub stantially as described.

5. The combination of the'rotatory screwcutting die, the rotating chuck, and the nonrotating pointing tool,. substantially as de scribed. y

6. The combination, with the chuck, `the turning-down tool, the screwcutting die, and the pointing-tool, of the automatic mechanism for bringing said tools into action inthe Order above named and in the-manner hereinbefore described.

7. The combination, with the chuck, the

lieving` and restoring the'bite ot the chuckjaws, and the mechanism through which the cam controls the said ch uckj' aws, of the swingingvlength-gage mounted upon a stationary tially as described. i

8. The combinati0n,withthe chuckadapted to receive a long rod or screw-stock, and the' feed weight and cord, of the 'slotted tube supported independently of the chuck. for upholding the end of the rodor screw-stoek out` iside the chuck-spindle, substantially as de-. scribed.

9. The turning-clown tool movable longitudinally and laterally with respect tothe screw-stock, in combinationl with the mech` anism Yfor moving the said tool slightly baek-r ward at the end of its cutting action, and then shifting it aside, substantially as described.

10. The combination, with the chuck, the longitudinal slide, the turning-down tool, the screw-cutting die placed immediately behind the turning-down tool, and the cam and ccnnections for operating said slideto bring said tools into action successively and by the same forward motion, of the separate cam and its lconnections for moving aside the turning-` down tool at the end of its cutting action, substantially as described. M

11. The combination, with the rock-shaft supporting the turning-clown tool, of the nut or sleeve engaging the said shaft for rocking the same and imparting thereto a slight endmotion Lin its bearings, substantially as described.

12. The combination, with the main slide, of the screw-cutting die, the auxiliary sli-de forming a support for said die, and movable in ways of the main slide, and the pointing tool supported on said main slide, substantially as described.

13. The combination of the rotating sleeve and clutch-piece for revolving the die with the rotating shaft inclosed in said sleeve, the non-rotating clutch-piece surrounding said,

sleeve, andthe clutch-piece revolved by said shaft, substantially as described.

14. The hollow screw-cutting die having cutting-jaws formed integral or in one piece therewith, and provided with an exterior ilange at the base for securing it in position inits support, substantially as described.

15. The herein-described automatic screwmachine, comprising the chuck adapted to re ceive a long rod or screw-stock, the lengthgage, the turning-down tool, the screw-cutting die, the pointingltool, the automatic mechan-l ism for releasing and restoring thebite of the chuck-jaws, the means for advancing the long .rod or screw-stock, the automatic mechanism for op erating thelengthgage, and the autom atie mechanism for operating the cutting-off tool,

5 automatic mechanism for revolving and holding stationary the die, and the automatic mechanism for moving aside the turning-down tool and for returning the same7 substantially as described.

16. In the screwcutting die having cuttingjaws formed in one piece with the body of the die and held in by pressure, the compressing means bearing mainly upon the front or cutting side of said jaws7 so ythat the rear or farther part may spring out more or less, and thereby give a slight twist to the jaws, substantially as described.

17. The combination, in a screw-cutting die7 of the jaws formed all in one piece, with the 2o compressingring having bearings upon said jaws mainly over the front or cutting edges l instead of over the whole width7 substantially as described.

18. In the screw-cutting die, the jaws cut away on the outside so as to leave them thickedges7 substantially as and for the purpose described.

419. The screw-cutting die comprising the jaws'formed in one pieceand screwthreaded on their exterior, and cut away so as to leave threaded bearing-surfaces only opposite the front or cutting edges7 in combination with est at points opposite the front or` cutting' the internally-threaded compressing-ring, sub- 

